#ifndef _PG_REGEX_H_
#define _PG_REGEX_H_			/* never again */
/*
 * regular expressions
 *
 * Copyright (c) 1998, 1999 Henry Spencer.  All rights reserved.
 * Portions Copyright (c) 2023-2025, IvorySQL Global Development Team
 *
 * Development of this software was funded, in part, by Cray Research Inc.,
 * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
 * Corporation, none of whom are responsible for the results.  The author
 * thanks all of them.
 *
 * Redistribution and use in source and binary forms -- with or without
 * modification -- are permitted for any purpose, provided that
 * redistributions in source form retain this entire copyright notice and
 * indicate the origin and nature of any modifications.
 *
 * I'd appreciate being given credit for this package in the documentation
 * of software which uses it, but that is not a requirement.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
 * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * src/include/regex/regex.h
 */

/*
 * This is an implementation of POSIX regex_t, so it clashes with the
 * system-provided <regex.h> header.  That header might be unintentionally
 * included already, so we force that to happen now on all systems to show that
 * we can cope and that we completely replace the system regex interfaces.
 *
 * Note that we avoided using _REGEX_H_ as an include guard, as that confuses
 * matters on BSD family systems including macOS that use the same include
 * guard.
 */
#ifndef _WIN32
#include <regex.h>
#endif

/* Avoid redefinition errors due to the system header. */
#undef REG_UBACKREF
#undef REG_ULOOKAROUND
#undef REG_UBOUNDS
#undef REG_UBRACES
#undef REG_UBSALNUM
#undef REG_UPBOTCH
#undef REG_UBBS
#undef REG_UNONPOSIX
#undef REG_UUNSPEC
#undef REG_UUNPORT
#undef REG_ULOCALE
#undef REG_UEMPTYMATCH
#undef REG_UIMPOSSIBLE
#undef REG_USHORTEST
#undef REG_BASIC
#undef REG_EXTENDED
#undef REG_ADVF
#undef REG_ADVANCED
#undef REG_QUOTE
#undef REG_NOSPEC
#undef REG_ICASE
#undef REG_NOSUB
#undef REG_EXPANDED
#undef REG_NLSTOP
#undef REG_NLANCH
#undef REG_NEWLINE
#undef REG_PEND
#undef REG_EXPECT
#undef REG_BOSONLY
#undef REG_DUMP
#undef REG_FAKE
#undef REG_PROGRESS
#undef REG_NOTBOL
#undef REG_NOTEOL
#undef REG_STARTEND
#undef REG_FTRACE
#undef REG_MTRACE
#undef REG_SMALL
#undef REG_OKAY
#undef REG_NOMATCH
#undef REG_BADPAT
#undef REG_ECOLLATE
#undef REG_ECTYPE
#undef REG_EESCAPE
#undef REG_ESUBREG
#undef REG_EBRACK
#undef REG_EPAREN
#undef REG_EBRACE
#undef REG_BADBR
#undef REG_ERANGE
#undef REG_ESPACE
#undef REG_BADRPT
#undef REG_ASSERT
#undef REG_INVARG
#undef REG_MIXED
#undef REG_BADOPT
#undef REG_ETOOBIG
#undef REG_ECOLORS
#undef REG_ATOI
#undef REG_ITOA
#undef REG_PREFIX
#undef REG_EXACT

/*
 * Add your own defines, if needed, here.
 */
#include "mb/pg_wchar.h"

/*
 * interface types etc.
 */

/*
 * regoff_t has to be large enough to hold either off_t or ssize_t,
 * and must be signed; it's only a guess that long is suitable.
 */
typedef long pg_regoff_t;

/*
 * other interface types
 */

/* the biggie, a compiled RE (or rather, a front end to same) */
typedef struct
{
	int			re_magic;		/* magic number */
	size_t		re_nsub;		/* number of subexpressions */
	long		re_info;		/* bitmask of the following flags: */
#define  REG_UBACKREF		000001	/* has back-reference (\n) */
#define  REG_ULOOKAROUND	000002	/* has lookahead/lookbehind constraint */
#define  REG_UBOUNDS		000004	/* has bounded quantifier ({m,n}) */
#define  REG_UBRACES		000010	/* has { that doesn't begin a quantifier */
#define  REG_UBSALNUM		000020	/* has backslash-alphanumeric in non-ARE */
#define  REG_UPBOTCH		000040	/* has unmatched right paren in ERE (legal
									 * per spec, but that was a mistake) */
#define  REG_UBBS			000100	/* has backslash within bracket expr */
#define  REG_UNONPOSIX		000200	/* has any construct that extends POSIX */
#define  REG_UUNSPEC		000400	/* has any case disallowed by POSIX, e.g.
									 * an empty branch */
#define  REG_UUNPORT		001000	/* has numeric character code dependency */
#define  REG_ULOCALE		002000	/* has locale dependency */
#define  REG_UEMPTYMATCH	004000	/* can match a zero-length string */
#define  REG_UIMPOSSIBLE	010000	/* provably cannot match anything */
#define  REG_USHORTEST		020000	/* has non-greedy quantifier */
	int			re_csize;		/* sizeof(character) */
	char	   *re_endp;		/* backward compatibility kludge */
	Oid			re_collation;	/* Collation that defines LC_CTYPE behavior */
	/* the rest is opaque pointers to hidden innards */
	char	   *re_guts;		/* `char *' is more portable than `void *' */
	char	   *re_fns;
} pg_regex_t;

/* result reporting (may acquire more fields later) */
typedef struct
{
	pg_regoff_t rm_so;			/* start of substring */
	pg_regoff_t rm_eo;			/* end of substring */
} pg_regmatch_t;

/* supplementary control and reporting */
typedef struct
{
	pg_regmatch_t rm_extend;	/* see REG_EXPECT */
} rm_detail_t;



/*
 * regex compilation flags
 */
#define REG_BASIC	000000		/* BREs (convenience) */
#define REG_EXTENDED	000001	/* EREs */
#define REG_ADVF	000002		/* advanced features in EREs */
#define REG_ADVANCED	000003	/* AREs (which are also EREs) */
#define REG_QUOTE	000004		/* no special characters, none */
#define REG_NOSPEC	REG_QUOTE	/* historical synonym */
#define REG_ICASE	000010		/* ignore case */
#define REG_NOSUB	000020		/* caller doesn't need subexpr match data */
#define REG_EXPANDED	000040	/* expanded format, white space & comments */
#define REG_NLSTOP	000100		/* \n doesn't match . or [^ ] */
#define REG_NLANCH	000200		/* ^ matches after \n, $ before */
#define REG_NEWLINE 000300		/* newlines are line terminators */
#define REG_PEND	000400		/* ugh -- backward-compatibility hack */
#define REG_EXPECT	001000		/* report details on partial/limited matches */
#define REG_BOSONLY 002000		/* temporary kludge for BOS-only matches */
#define REG_DUMP	004000		/* none of your business :-) */
#define REG_FAKE	010000		/* none of your business :-) */
#define REG_PROGRESS	020000	/* none of your business :-) */



/*
 * regex execution flags
 */
#define REG_NOTBOL	0001		/* BOS is not BOL */
#define REG_NOTEOL	0002		/* EOS is not EOL */
#define REG_STARTEND	0004	/* backward compatibility kludge */
#define REG_FTRACE	0010		/* none of your business */
#define REG_MTRACE	0020		/* none of your business */
#define REG_SMALL	0040		/* none of your business */


/*
 * error reporting
 * Be careful if modifying the list of error codes -- the table used by
 * regerror() is generated automatically from this file!
 */
#define REG_OKAY	 0			/* no errors detected */
#define REG_NOMATCH  1			/* failed to match */
#define REG_BADPAT	 2			/* invalid regexp */
#define REG_ECOLLATE	 3		/* invalid collating element */
#define REG_ECTYPE	 4			/* invalid character class */
#define REG_EESCAPE  5			/* invalid escape \ sequence */
#define REG_ESUBREG  6			/* invalid backreference number */
#define REG_EBRACK	 7			/* brackets [] not balanced */
#define REG_EPAREN	 8			/* parentheses () not balanced */
#define REG_EBRACE	 9			/* braces {} not balanced */
#define REG_BADBR	10			/* invalid repetition count(s) */
#define REG_ERANGE	11			/* invalid character range */
#define REG_ESPACE	12			/* out of memory */
#define REG_BADRPT	13			/* quantifier operand invalid */
#define REG_ASSERT	15			/* "can't happen" -- you found a bug */
#define REG_INVARG	16			/* invalid argument to regex function */
#define REG_MIXED	17			/* character widths of regex and string differ */
#define REG_BADOPT	18			/* invalid embedded option */
#define REG_ETOOBIG 19			/* regular expression is too complex */
#define REG_ECOLORS 20			/* too many colors */
/* two specials for debugging and testing */
#define REG_ATOI	101			/* convert error-code name to number */
#define REG_ITOA	102			/* convert error-code number to name */
/* non-error result codes for pg_regprefix */
#define REG_PREFIX	(-1)		/* identified a common prefix */
#define REG_EXACT	(-2)		/* identified an exact match */

/*
 * all the options of interest for regex functions.
 * move from regexp.c to here.
 */
typedef struct pg_re_flags
{
	int			cflags;			/* compile flags for Spencer's regex code */
	bool		glob;			/* do it globally (for each occurrence) */
} pg_re_flags;

/* Redirect the standard typenames to our typenames. */
#define regoff_t pg_regoff_t
#define regex_t pg_regex_t
#define regmatch_t pg_regmatch_t


/*
 * the prototypes for exported functions
 */

/* regcomp.c */
extern int	pg_regcomp(regex_t *re, const pg_wchar *string, size_t len,
					   int flags, Oid collation);
extern int	pg_regexec(regex_t *re, const pg_wchar *string, size_t len,
					   size_t search_start, rm_detail_t *details,
					   size_t nmatch, regmatch_t pmatch[], int flags);
extern int	pg_regprefix(regex_t *re, pg_wchar **string, size_t *slength);
extern void pg_regfree(regex_t *re);
extern size_t pg_regerror(int errcode, const regex_t *preg, char *errbuf,
						  size_t errbuf_size);

/* regexp.c */
extern regex_t *RE_compile_and_cache(text *text_re, int cflags, Oid collation);
extern bool RE_compile_and_execute(text *text_re, char *dat, int dat_len,
								   int cflags, Oid collation,
								   int nmatch, regmatch_t *pmatch);

extern regex_t *ora_re_compile_and_cache(text *text_re, int cflags, Oid collation);
extern void ora_parse_re_flags(pg_re_flags *flags, text *opts);
extern text *ora_replace_text_regexp(text *src_text, regex_t *regexp,
				   text *replace_text, int start_posn,int occur_posn);
extern bool
ora_substr_text_regexp(text *src_text,text *pattern_arg ,text *match_para,
								   Oid collation,int start_posn,
								   int occur_posn,int subexpr_pos,
								   Datum *substr);
extern bool
ora_setup_regexp_substr_matches(text *src_text, regex_t *re, pg_re_flags re_flags,
											 int start_posn, int occur_posn,
											 int subexpr_pos,Datum *substr,
											 bool ignore_degenerate);
extern int charlen_to_bytelen(const char *p, int n);

extern bool
ora_instr_text_regexp(text *src_text,text *pattern_arg ,text *match_para,
								 Oid collation,int start_posn,
								 int occur_posn,int ret_opt,
								 int subexpr_pos,Datum *substr);
extern bool
ora_setup_regexp_instr_matches(text *src_text, regex_t *re, pg_re_flags re_flags,
										   int start_posn, int occur_posn,
										   int ret_opt,int subexpr_pos,
										   Datum *substr,bool ignore_degenerate);


#endif							/* _REGEX_H_ */
